#5429: Fix a module initialisation order problem - if the eclass modu…

…le gets initialised before the VFS is initialised, no files are parsed.

include/ifilesystem.h

@@ -143,10 +143,16 @@ class VirtualFileSystem :
 	// Initialises the filesystem using the given search order.
 	virtual void initialise(const SearchPaths& vfsSearchPaths, const ExtensionSet& allowedArchiveExtensions) = 0;
 
+    // Returns true if the filesystem has already been initialised
+    virtual bool isInitialised() const = 0;
+
 	/// \brief Shuts down the filesystem.
 	virtual void shutdown() = 0;
 
 	// greebo: Adds/removes observers to/from the VFS
+    // Observers should also check isInitialised() after adding themselves
+    // since the VFS might have been initialised already. Calling addObserver()
+    // won't call onFileSystemInitialise() if that's the case.
 	virtual void addObserver(Observer& observer) = 0;
 	virtual void removeObserver(Observer& observer) = 0;
 

radiantcore/eclass/EClassManager.cpp

@@ -290,7 +290,11 @@ void EClassManager::initialiseModule(const IApplicationContext& ctx)
 	rMessage() << "EntityClassDoom3::initialiseModule called." << std::endl;
 
 	GlobalFileSystem().addObserver(*this);
-	realise();
+
+    if (GlobalFileSystem().isInitialised())
+    {
+        realise();
+    }
 
 	GlobalCommandSystem().addCommand("ReloadDefs", std::bind(&EClassManager::reloadDefsCmd, this, std::placeholders::_1));
 }

radiantcore/vfs/Doom3FileSystem.cpp

@@ -304,7 +304,7 @@ void Doom3FileSystem::initialise(const SearchPaths& vfsSearchPaths, const Extens
         return;
     }
 
-    if (!_vfsSearchPaths.empty())
+    if (isInitialised())
     {
         // We've been initialised with some paths already, shutdown first
         shutdown();
@@ -336,6 +336,11 @@ void Doom3FileSystem::initialise(const SearchPaths& vfsSearchPaths, const Extens
     }
 }
 
+bool Doom3FileSystem::isInitialised() const
+{
+    return !_vfsSearchPaths.empty();
+}
+
 void Doom3FileSystem::shutdown()
 {
     for (Observer* observer : _observers)

radiantcore/vfs/Doom3FileSystem.h

@@ -32,6 +32,7 @@ class Doom3FileSystem :
 
 public:
 	void initialise(const SearchPaths& vfsSearchPaths, const ExtensionSet& allowedExtensions) override;
+    bool isInitialised() const override;
 	void shutdown() override;
 
 	int getFileCount(const std::string& filename) override;